Connector for making an optical connection underwater

ABSTRACT

A connector for making an optical connection underwater or in a wet environment, including first and second connector parts adapted to be interengaged, the first connector part having a probe and the second connector part having a chamber containing fluid media. The probe has a forward portion for entry into the chamber of the second part containing fluid media during interengagement of the connector parts, so that when the connector parts are interengaged the probe provides an optical path between the first connector part and the chamber of the second connector part and passing into the chamber of the second connector part at a slant to the axial direction. The probe slides axially through the opening in sliding engagement with a seal and continues to do so as the forward portion of the probe advances into the chamber containing fluid media.

[0001] This invention relates to an optical connector for making anoptical connection underwater or in a wet environment.

[0002] Optical fibres are frequently used for communication purposes,and it is often necessary to form an optical connection between the endsof such fibres. This generally involves bringing together two connectorcomponents each supporting a respective fibre and making end-to-endcontact between the fibres. In the case of underwater connectors, it isknown to provide the connector components with end sealing arrangementsso that the optical fibre ends are protected from the outsideenvironment when the components are in a disconnected state, the endsealing arrangements opening up during connection to allow passage ofone of the optical fibre ends therethrough in order to establish theoptical connection.

[0003] It has been proposed for example in U.S. Pat. No. 4,887,883 toprovide the two connector components of an underwater optical fibreconnector with end sealing arrangements each comprising a relativelythick (in the axial direction) seal member with an axial opening formedtherethrough. The axial openings are kept closed by the resilience ofthe seal members when the components are disconnected, and duringconnection a wand structure supporting an optical fibre pushes its waythrough the mating seal members of the two components. The axiallydirected optical end face of the optical fibre then makes contact withthe end face of the optical fibre in the other connector component.However, with such an arrangement there is a risk of damage to theoptical end faces of the optical fibres caused by particles of sand,silt or the like which have lodged on the seal members. Such particlesmay be transferred on to the end face of the wand supported opticalfibre as it forces its way through the seal members and may be carriedforward and sandwiched between that end face and the end face of theother optical fibre.

[0004] Another arrangement using the idea of sealed chambers which openup during mating to enable an optical connection to be made betweenaxially directed end faces of optical fibres is disclosed in WO-A-9 622554. During connection, the end of a wand supporting an optical fibre inone connector component exits a chamber of that component and enters achamber in the other component. In this arrangement, instead of havingresilient seal members with axial openings which have to be forced openby the wand, each connector component has a laterally movable gate foropening up the respective chamber during mating. During connection, themovable gate of the chamber housing the wand end opens first, the wandend passes through a region containing ambient water, and the movablegate of the other chamber opens to allow entry of the wand. The wandthen passes axially along an oil-filled tube of about the same diameteras the wand, forcing oil out of the tube via a side vent, untilend-to-end engagement is made between the respective optical fibres.With such an arrangement, if the ambient water contains debris such assand, silt or the like, then there is again a risk that particles ofdebris will lodge against the end face of the wand supported opticalfibre and then be carried forward along the oil-filled tube to besandwiched between that end face and the end face of the other opticalfibre. Further, the mechanism and sealing arrangement is complex whichis not desirable in subsea operations.

[0005] Alternative underwater optical connectors have been proposed inWO-A-8 500 899 and GB-A-2 166 261 having laterally facing optical endfaces rather than axially directed end faces. In these arrangements aprobe belonging to a male connector component is arranged to push back astopper piston of a female connector component to enable a laterallyfacing optical end face on the probe to form an optical coupling with alaterally facing optical end face in the female connector component. Inthe disconnected condition, the optical end face of the probe is coveredby a sleeve. During connection, the sleeve slides back axially along theprobe, during which action a wiper passes over the optical end face towipe it. Similarly, a wiper on the stopper piston wipes the optical endface in the female connector component as the stopper piston is pushedback. Although these known proposals avoid the problem of debrisbecoming lodged on an axial end face of an optical member when itemerges from its housing, they rely on the effectiveness of the wipingaction, and if the wipers deteriorate with time the optical coupling maybecome contaminated. Moreover, in the connected condition of theconnector, the region where the optical coupling is made is not sealedfrom the outside and may therefore be subject to entry of contaminants.

[0006] Another optical connector has been proposed in WO 98/45899, inwhich the use of axially directed end faces of the optical components tobe connected is avoided. In this arrangement a female connectorcomponent has a plurality of optical contacts arranged in an annularchamber in a housing, at circumferential intervals around the outside ofa retractable cover sleeve, and pointing inwardly towards the coversleeve. A male connector component has an axially centrally arrangedpusher member, also provided with a retractable cover sleeve. Aplurality of flexible tubes holding optical fibres are supported atcircumferential intervals around the outside of the rear of the pushermember and project forwardly in cantilever fashion. The flexible tubesextend radially outwardly as well as forwardly in such a way that theirown resilience urges them against the inside of the cover sleeve. Whenthe male and female connector components are to be mated, a seal ring onthe pusher member engages the cover sleeve of the female connectorcomponent, whilst a seal ring on the housing of the female connectorcomponent engages the cover sleeve of the male connector component. Withfurther axial interengagement, the pusher member pushes the female coversleeve rearwardly to retract it, and the female housing pushes the malecover sleeve rearwardly to retract that sleeve. Eventually, the annularchamber where the optical contacts of the female connector component arehoused is joined with the region where the cantilevering flexible tubesof the male connector component are supported. The flexible tubes arereleased from being held down by the male cover sleeve and splayoutwardly into internal guide grooves in the female housing. Opticalcontacts at the ends of the flexible tubes then complete opticalcircuits with the optical contacts of the female component.

[0007] According to an aspect of the invention there is provided aconnector for making an optical connection underwater or in a wetenvironment, comprising a probe on a first connector part arranged topass through a seal on a second connector part, so as to provide anoptical path which extends through a side of the probe. The optical pathis preferably arranged to be slanted to the axis of the probe at leastwhere it extends through the side thereof.

[0008] By arranging the optical path to extend through a side of theprobe and preferably at a slant to the axial direction, rather thanhaving axially directed optical end faces, the risk of damage or signalattenuation caused by particles of sand, silt or the like being trappedbetween such end faces is minimised.

[0009] According to another aspect of the invention there is provided aconnector for making an optical connection underwater or in a wetenvironment, comprising first and second connector parts adapted to beinterengaged, the first connector part having a first optical member forestablishing an optical coupling with a second optical member of thesecond connector part when the connector parts are interengaged, thefirst connector part having a probe and the second connector part havinga chamber containing fluid media and being provided with a seal definingan opening thereto, wherein the probe has a forward portion for entryinto the chamber of the second part containing fluid media duringinterengagement of the connector parts, so that when the connector partsare interengaged the probe provides an optical path between the firstconnector part and the chamber of the second connector part and therebyallows the first and second optical members to establish said opticalcoupling, said optical path extending from the first connector partalong the probe and passing into the chamber of the second connectorpart at a slant to the axial direction, and wherein duringinterengagement of the connector parts the probe slides axially throughthe opening in sliding engagement with the seal and continues to do soas the forward portion of the probe advances into the said chambercontaining fluid media.

[0010] The probe of the first connector part thus gains access to thechamber of the second connector part and provides an optical pathbetween the connector parts allowing the optical coupling to beestablished. When the connector parts are interengaged the probe extendsthrough the opening to the chamber of the second connector part insealing engagement with the seal, and thus achieves sealed communicationbetween the two connector parts in a simple manner.

[0011] The connector may be arranged so that after the probe has enteredthe chamber of the second connector part the second optical member movesforwardly via the probe into the first connector part where the opticalcoupling between the first and second optical members is established.Preferably, however, the first optical member enters the chamber of thesecond connector part and the optical coupling between the first andsecond optical members is established therein.

[0012] In preferred arrangements, the first optical member is disposedinternally of the probe at least during the passage of the probe throughthe seal at the opening to the chamber of the second connector part.This can ensure protection of the first optical member during the matingprocedure, for example from debris which has lodged on the unmatedcomponents.

[0013] The first optical member may be exposed at a side opening of theprobe ready for coupling with the second optical member. Preferably,however, the probe comprises relatively movable parts arranged toenclose the first optical member when the first and second connectorparts are not interengaged and arranged to open after the probe hasentered the chamber of the second connector part to allow the opticalcoupling between the first and second optical members to be established.In this way, as the probe slides axially through the opening to thesecond connector part chamber in sliding engagement with the seal duringthe interengagement procedure, the probe can substantially maintainsealing engagement with the seal and thus keep the chamber sealedagainst ingress of debris. One of the relatively movable parts of theprobe may take the form of a cover arranged to pivot laterally outwardlyto effect the desired opening, or there may be a cover which is axiallyretractable relative to the rest of the probe.

[0014] In a preferred arrangement, the connector comprises a firstspring arranged to deform during a first phase of interengagement of theconnector parts until the forward portion of the probe is located in thechamber of the second connector part containing fluid media, and asecond spring arranged to deform during a second phase ofinterengagement of the connector parts to permit the forward portion ofthe probe to advance forwardly relative to a rear portion and therebyallow the optical coupling between the first and second optical membersto be established.

[0015] The optical members to be coupled may not have to make physicalcontact with each other, for example if they comprise expanded beamterminations, such as a plano-convex rod lens, a graded index (GRIN) rodlens, or a spherical lens. It is currently preferred to use feruleswhich are brought into physical contact to establish the opticalcoupling. It is generally useful to provide an arrangement in which oneof the optical members can be moved to assist this. Preferably, afterthe probe has entered the chamber of the second connector part, at leastone of the first and second optical members is arranged to move from aretracted position to a coupling position. The optical member inquestion may be kept in the retracted position during the initialinterengagement procedure, keeping it protected from any debris. It maythen advance to the coupling position to establish the optical couplingonce the probe interconnects the two connector parts.

[0016] In preferred arrangements, it is the first optical member whichis arranged to move relative to the probe from said retracted positionto said coupling position, the first optical member protruding laterallyfrom a side of the probe when in the coupling position.

[0017] It is particularly preferred for the first optical member to bearranged to move relative to a guide portion of the probe duringinterengagement of the connector parts, the guide portion being arrangedto urge the first optical member laterally outwardly of the probe from aretracted position to a coupling position during said interengagement.Thus, the first optical member is urged to its coupling position duringinterengagement, and preferably also urged to its retracted positionduring disengagement, by the guide portion. This gives a controlledmovement and ensures reliable establishment of the optical coupling.Further, by not relying on the resilience of a flexible tube to move thefirst optical member to its coupling position, the possibility ofpermanent set or relaxation occurring in such a flexible tube if theconnector is left unmated for some time, preventing correct operation,is eliminated. Preferably, the probe has a surface slanted relative tothe axial direction which guides the first optical member to thecoupling position.

[0018] Although the first optical member may be supported on a flexiblesupport, it is preferably supported on a rigid support in order toassist with alignment accuracy when establishing the optical coupling.The rigid support may be at a fixed angle to the axial direction andarranged to move laterally to establish the optical coupling, forexample by using a camming arrangement.

[0019] It is further preferred for the first optical member to besupported by the probe at, or adjacent to, a region where the opticalcoupling with the second optical member is established. If by contrastthe first optical member were supported by the probe at a large distancefrom where it couples with the second optical member, there is somepotential for misalignment of the optical members. Such risk ofmisalignment may be substantially minimised with the preferredarrangement.

[0020] The seal at the chamber opening of the second connector part maybe of the type which is self-closing, for example by virtue of theresilience of the material of which it is made, and which can be forcedopen by the probe during interengagement of the connector parts. It ishowever preferred to provide the second connector part with a shuttlepiston resiliently biased to a forward position in which it engages aradially inwardly facing surface of the seal so as to close the openingdefined thereby when the connector parts are disengaged, the shuttlepiston being arranged to be engaged by the probe and urged rearwardlyduring interengagement of the connector parts, the probe then engagingthe radially inwardly facing surface of the seal so as to close theopening defined thereby. With such an arrangement, the shuttle pistonblocks the chamber opening when the connector parts are disengaged, andthe probe can block the chamber entrance when the connector parts areinterengaged.

[0021] According to a further aspect of the invention, there is provideda connector for making an optical connection underwater or in a wetenvironment, comprising first and second connector parts adapted to beinterengaged, the first connector part having a first optical member forestablishing an optical coupling with a second optical member of thesecond connector part when the connector parts are interengaged, thesecond connector part having a chamber containing fluid media and beingprovided with a seal defining an opening thereto, and the secondconnector part being provided with a shuttle piston resiliently biasedto a forward position in which it engages a radially inwardly facingsurface of the seal so as to close the opening defined thereby when theconnector parts are disengaged, and the first connector part having aprobe for entry into the chamber of the second part containing fluidmedia during interengagement of the connector parts, the shuttle pistonof the second connector part being arranged to be engaged by the probeand urged rearwardly during said interengagement, the probe thenengaging the radially inwardly facing surface of the seal so as to closethe opening defined thereby, and, when the connector parts areinterengaged, the probe providing an optical path between the firstconnector part and the chamber of the second connector part to allow thefirst and second optical members to establish said optical coupling,said optical path extending from the first connector part along theprobe and passing into the chamber of the second connector part at aslant to the axial direction.

[0022] The second connector part preferably comprises pressure balancingmeans for allowing pressure in the chamber to balance relative toexternal pressure. Such pressure balancing may be provided by e.g. apiston and cylinder arrangement but preferably the chamber has aflexible wall portion to provide pressure balancing. An advantage of apressure balanced system is that this reduces any tendency for water orcontaminants to enter the chamber e.g. via the opening thereto,particularly during interengagement when the probe enters the chamber.In addition, by avoiding any substantial pressure difference across theseal at the chamber entrance, the probe can move relatively freely intoand out of the chamber.

[0023] The second connector part may be provided with a single chambercontaining fluid media. Preferably the chamber of the second connectorpart comprises an outer sub-chamber and an inner sub-chamber. The use ofa probe to provide an optical path allows for the incorporation of morethan one sub-chamber without over complicating the overall design of theconnector. This is generally not the case in the prior art connectors.The ability to provide more than one sub-chamber is a significantadvantage of the use of a probe which slides axially into the secondconnector part.

[0024] In preferred embodiments, the outer sub-chamber is provided withsaid seal defining said chamber opening, and the inner sub-chamber isprovided with a seal defining an inner sub-chamber opening, and whereinduring interengagement of the connector parts the probe slides axiallythrough the outer and inner sub-chamber openings and in slidingengagement with their respective seals, whilst the forward portion ofthe probe advances into the inner sub-chamber. Preferably the outer andinner sub-chambers are pressure balanced. They may for example haverespective flexible wall portions exposed to external pressure, or theinner sub-chamber may have a flexible wall portion exposed to the fluidmedia in the outer sub-chamber.

[0025] A plurality of probes may be provided for providing a pluralityof optical paths. A separate inner sub-chamber may be provided toreceive each probe. Thus if sealing integrity of one inner sub-chamberis compromised this need not compromise any other inner sub-chamber.

[0026] It is preferred for the first connector part to comprise a probechamber in which the first optical member is disposed when the connectorparts are not interengaged, the probe chamber and the probe beingrelatively axially movable to allow the probe to emerge from the probechamber during interengagement of the connector parts, and the probechamber containing fluid media. The first optical member can thus bekept in a protected condition when the connector parts are disengaged.

[0027] The probe chamber is preferably provided with an opening theretothrough which the probe passes axially during interengagement of theconnector parts, with a probe seal being provided at the probe chamberopening, wherein when the connector parts are interengaged the probeextends through the opening in sealing engagement with the probe seal.

[0028] The seal at the probe chamber opening may be of the type which isself-closing, for example by virtue of the resilience of the material ofwhich it is made, and which can be forced open by the probe duringinterengagement of the connector parts. It is however preferred for theprobe to be arranged to block the probe chamber opening when theconnector parts are disengaged, and for the probe also to block theprobe chamber opening when the connector parts are interengaged.

[0029] Preferably, the first connector part further comprises pressurebalancing means for allowing pressure in the probe chamber to balancerelative to external pressure. Such pressure balancing may be providedby e.g. a piston and cylinder arrangement but preferably the probechamber has a flexible wall portion to provide pressure balancing. Anadvantage of a pressure balanced system is that this reduces anytendency for water or contaminants to enter the probe chamber,particularly during disengagement when the probe withdraws into theprobe chamber. In addition, by avoiding any substantial pressuredifference across a seal at the probe chamber opening, the probe canmove relatively freely out of and into the probe chamber.

[0030] The first connector part may be provided with a single probechamber containing fluid media. Preferably the probe chamber of thefirst connector part comprises an outer sub-chamber and an innersub-chamber. The use of a probe to provide an optical path allows forthe incorporation of more than one probe sub-chamber without overcomplicating the overall design of the connector. This is generally notthe case in the prior art connectors.

[0031] In preferred embodiments, the outer and inner sub-chambers of theprobe chamber are provided with respective seals defining respectiveopenings thereto, and wherein during interengagement of the connectorparts the probe slides axially through the inner and outer probesub-chamber openings in sliding engagement with their respective seals.Preferably the probe outer and inner sub-chambers are pressure balanced.They may for example have respective flexible wall portions exposed toexternal pressure, or the probe inner sub-chamber may have a flexiblewall portion exposed to the fluid media in the probe outer sub-chamber.

[0032] Where a plurality of probes are provided for providing aplurality of optical paths, a separate probe inner sub-chamber may beprovided to receive each probe. Thus if sealing integrity of one probeinner sub-chamber is compromised this need not compromise any otherprobe inner sub-chamber.

[0033] It is preferred for the chamber of the second connector part andthe chamber of the first connector part to be sealed from each otherwhen the first and second connector parts are interengaged. Thisimproves the sealing properties of the connector. In particular, if theintegrity of the probe chamber is compromised, this will not affect theintegrity of the chamber of the second connector, where the opticalcoupling will normally be established.

[0034] The connector may provide for an optical coupling only, but it ispreferred to provide a combined electrical and optical connector, i.e.an electro-optical connector. An electrical path may be provided forexample by a separate electrical probe, for making electrical contactwith an electrical socket of the other connector part, for example ofthe type known from GB-A-2 192 316. Preferably, the probe which providesthe optical path is provided with a first electrical contact portion,and the second connector part has a second electrical contact portion,the first and second electrical contact portions being arranged to makeelectrical contact when the connector parts are interengaged. Such anarrangement provides a significant advance over the known opticalconnectors, because the probe which is used to provide the optical pathis also used to provide an electrical path. The size of the electricalpath is not limited by the size of the opening in a laterally movablegate, as in WO-A-9 622 554, nor by the size of the flexible tubecantilevers as in WO 98/45899. In the absence of the size constraintsimposed by the prior art designs, relatively high current ratings can beachieved using a given probe, whilst also providing an optical path.Thus, both the optical and the electrical paths may be provided using asingle probe. Conveniently the electrical contact may be made in thechamber of the second connector part, in which case the fluid media inthe chamber will be a dielectric.

[0035] The first electrical contact portion may be provided on the sideof the probe, for example as a contact ring. The second electricalcontact portion may then be a contact socket in which the ring isengageable. Alternatively, the first electrical contact portion may beprovided at the front of the probe. This arrangement is however lesspreferred, since it means that when disconnected the first electricalcontact would be exposed to the outside.

[0036] In the preferred embodiment where the second connector part hasan inner sub-chamber which is entered by the probe, the secondelectrical contact portion may be provided in the outer sub-chamber, butpreferably it is provided in the inner sub-chamber. Where the firstconnector part has probe outer and inner sub-chambers, when theconnector parts are disconnected the first electrical contact portionmay be located in the outer sub-chamber, but preferably it is located inthe inner sub-chamber. Thus in a particularly preferred embodiment, thefirst optical member and the first electrical contact are both arrangedin a probe inner sub-chamber when the connector parts are disconnected,and the second optical member and the second electrical contact are botharranged in an inner sub-chamber of the second connector part when theconnector parts are interengaged. Thus there is a dual barrier betweenthe optical and electrical components and the outside throughout.

[0037] The fluid media in the chamber may be gel or oil or the like. Itsrefractive index, together with that of all other optical components,will be appropriately selected to optimise light transmission throughthe connector.

[0038] Certain preferred embodiments of the invention will now bedescribed, by way of example only, and with reference to theaccompanying drawings, in which:

[0039]FIG. 1 is a longitudinal sectional view of a first connector part,taken on the lines I-I of FIG. 3;

[0040]FIG. 2 is a longitudinal sectional view of the first connectorpart, taken on the lines II-II of FIG. 3;

[0041]FIG. 3 is an end view of the first connector part;

[0042]FIG. 4 is a top view of a probe of the first connector part;

[0043]FIG. 5 is a longitudinal sectional view along the centre line ofFIG. 4, showing the probe with the optical contact in a retractedposition;

[0044]FIG. 6 is a longitudinal sectional view on the centre line of FIG.3, showing the probe in a coupling position;

[0045]FIG. 7 is a longitudinal sectional view of a second connectorpart, taken along the lines VII-VII of FIG. 9;

[0046]FIG. 8 is a longitudinal sectional view of the second connectorpart, taken along the lines VIII-VIII of FIG. 9;

[0047]FIG. 9 is an end view of the second connector part;

[0048]FIG. 10 is a perspective view of the interior of the secondconnector part, with parts removed for clarity;

[0049]FIG. 11 is an end view of the interior of the second connectorpart;

[0050]FIG. 12 is a longitudinal sectional view of the first and secondconnector parts prior to interengagement;

[0051]FIG. 13 is a longitudinal sectional view of the first and secondconnector parts at a first stage of interengagement;

[0052]FIG. 14 is a longitudinal sectional view of the first and secondconnector parts when fully interengaged;

[0053]FIG. 15 is an exploded perspective view of the construction of theprobe of the first connector part;

[0054]FIG. 16 is an exploded perspective view of an alternative form ofprobe construction;

[0055]FIG. 17 is a top view of another embodiment of the probe;

[0056]FIG. 18 is a longitudinal sectional view along the centre line ofFIG. 17, showing the optical member in a retracted position;

[0057]FIG. 19 is a view similar to FIG. 18 but showing the opticalmember in a coupling position;

[0058]FIGS. 20a-20 d are schematic longitudinal views, partly in sectionand partly in elevation, of another embodiment showing first and secondconnector parts at different stages during the connection procedure;

[0059]FIGS. 21a-21 d are longitudinal sectional views, partly in sectionand partly in elevation, of another embodiment showing first and secondconnector parts at different stages during the connection procedure;

[0060]FIG. 22 is a longitudinal elevation view of an outer sleeve of thefirst connector part of FIGS. 21a-21 b;

[0061]FIG. 23 is a longitudinal elevation view of an inner body of thefirst connector part of FIGS. 21a-21 d; and

[0062]FIGS. 24a-24 d are longitudinal views, partly in section andpartly in elevation, of first and second connector parts of anotherembodiment at different stages during the connection procedure.

[0063] The embodiment shown in FIGS. 1 to 14 will now be described.FIGS. 1 to 3 show a first connector part 2 having a receptacle 4 forreceiving a plug 6 of a second connector part 8, shown in FIGS. 7 to 9.An axially arranged probe 10 projects forwardly from a rear support 12.An optical fibre 16 extends into the probe 10 via a rear opening 11plugged by an epoxy water block and along a passage 18 in the probe toan optical contact 20 housed in a slanted passage 22 of the probe. Atthe front end of the optical contact 20, an optical pin 21 is provided.A front opening 27 is provided at the forward end of the slanted passage22, where a seal 216 is also provided.

[0064] The construction of the probe 10 is best seen in FIGS. 4 to 6 and15. At its forward end the probe has a nose portion 200. Behind it anelectrical probe contact portion 202 is provided. The probe contactportion 202 is supported at the front end of a pair of axially extendingconductive arms 204 which extend inside a sliding sleeve 206 made ofinsulating material. At its rear the sliding sleeve has a rear shoulder207 which engages the front end of a spring 208, the rear end of whichengages a shoulder 210 provided at the rear of the conductive arms 204.The nose portion 200, the probe contact portion 202 and the conductivearms 204 are all fixed in position within the receptacle 4, with thesliding sleeve being rearwardly slidable with respect thereto.

[0065] The optical contact 20 is supported in a rigid optical contactsupport tube 212, the front end of which engages in the slanted passage22, which is formed in the sliding sleeve 206. The optical contact 20 isthus supported at an angle to the axial direction. A pair of outwardlydirected lugs 214 are provided at the rear of the support tube 212 andengage in respective transverse slots 216 formed in the conductive arms204. At the front face of the sliding sleeve 206 the seal 216 isprovided.

[0066] As seen in FIG. 15 the conductive arms 204 are provided as twoseparate members, to which the pin contact end 202 is secured by a pressfit pin 218 in electrically conductive manner. The sliding sleeve 206 isformed with a pair of axial passages 220 for receiving the respectiveconductive arms 204. The optical contact support tube 212 and the arms204 pass through respective openings in the seal 216 in sealing manner.

[0067] In the version of FIG. 16, instead of the conductive arms 204, asingle part-circular arm 205 is provided and a single passage 220 ofcorresponding shape is provided in the sliding sleeve 206. Also, acorrespondingly shaped opening is provided in the seal 216 to receivethe single arm 205 in sealing manner. The rear of the arm 205 isconductively connected to a rear shoulder member 211.

[0068] The optical contact 20 is contained within the periphery of theprobe 10 when viewed in the axial direction, when the connector partsare disconnected as shown in FIGS. 1, 2 and 4. It therefore does notprotrude from the probe. An electrical line extends rearwardly from theconductive arms 204 to a solder cup at the rear of the first connectorpart.

[0069] A shuttle 24 is slidably supported in the receptacle 4 of thefirst connector part 2. The shuttle 24 is forwardly biased by a spring26 which seats against the support 12 at the rear. The spring 26 urgesthe shuttle 24 forwardly such that a pair of radially inwardlyprojecting keys 28 of the receptacle 4 engage the rear ends ofrespective keyways 29 in the outside wall of the shuttle 24, therebydefining the forward position of the shuttle 24. The key and keywayarrangement also prevents rotation of the shuttle in the receptaclewhilst allowing longitudinal movement thereof.

[0070] The shuttle 24 has a rear wall 30 to which the probe 10 isslidably sealed by a pair of O-ring seals 32. The shuttle defines achamber 34 around the front of the probe 10 (“the probe chamber”). Theprobe chamber 34 is defined within a bladder 36 filled with fluid media.The bladder 36 has a thick front wall 38 formed with an opening 40 whichis sealingly engaged by the front end of the probe 10. The bladder has athinner side wall 42 extending to a rear flange 44 captured between rearwall 30 and a bladder retaining sleeve 46. The bladder retaining sleeveis supported by an outer sleeve 48 of the shuttle 24 and is formed withradial ports (not shown) communicating with radial ports (not shown) inouter sleeve 48 between the sleeves 46 and 48. The outer sleeve 48 isexposed to the ambient water in receptacle 4 via radial ports 53. Theoutside of bladder side wall 42 is therefore effectively exposed tooutside pressures and thus allows volume changes within probe chamber 34to equalise the pressure therein with external pressure, therebyminimising any tendency for outside water or other contaminants to enterprobe chamber 34.

[0071] The probe chamber 34 comprises an outer sub-chamber 56 and fourinner sub-chambers 58. Each inner sub-chamber is defined by an innerbladder 60 which is seated on rear wall 30 and projects forwardlytherefrom. The inner bladder 60 has a thick front wall 62 formed with anopening 64 through which the probe 10 passes in slidable and sealingmanner. The inner bladder 60 has a thinner side wall 66 supported on aninner bladder sleeve 68, which is formed with radial ports (not shown)to communicate the side wall 66 with the interior of the sub-chamber 58.The outside of bladder side wall 66 is exposed to the pressure in theouter sub-chamber 56, thereby enabling inner sub-chamber 58 to equaliseits pressure relative to outer sub-chamber 56. Outer sub-chamber 56 isable to equalise its pressure relative to the outside by exposure ofbladder side wall 42 to outside pressure via the previously describedradial ports.

[0072] Both the front opening 27 of optical fibre passage 22 and theelectrical contact 25 are located in the inner sub-chamber 58 when theconnector parts are disconnected, as shown in FIGS. 1, 2 and 4.

[0073] The second connector part 8 will now be described. The plug 6 hasan orientation key 126 for engagement in a corresponding keyway 128 ofthe receptacle 4. A fibre optic 76 extends forwardly from an epoxy waterblock 300 into a chamber 78 at the front of the plug 6. At its front endthe fibre optic 76 is provided with an optical contact 80 arranged at anangle to the axial direction. The optical contact includes a spring 82allowing rearward resilient movement of a contact socket 84 at the frontof the optical contact. This is a known optical contacting arrangement.The optical contact 80 and its mounting arrangement are supported on anoptical contact support 81.

[0074] The chamber 78 containing fluid media is defined within a bladder86 having a thick front wall 88 formed with an opening 90 in which ashuttle piston 92 is sealingly engaged. An electrical contact ring 130is provided towards the rear of the shuttle piston 92 and is connectedto a solder cup 132 at the back of the plug 6. The bladder 86 has acircumferentially extending thinner side wall 94 terminating at its rearwith a flange 96 captured between a rear wall 98 and a bladder retainingsleeve 100. The retaining sleeve 100 is formed with radial ports 102 andthe plug 6 is formed with radial ports 104. The outside of the side wall94 of the bladder is thus communicated with the outside via radial ports102, a radial gap 106 between the bladder retaining sleeve 100 and theinside of plug 6, and the radial ports 104 through the plug. Thecommunication of the outside of the bladder 86 with the outsideenvironment allows the bladder to change in volume in response toexternal pressure changes and displacements due to entry of the probe10. The pressure in chamber 78 may thus be equalised with externalpressure so as to minimise any opportunity for external water orcontaminants to enter the chamber.

[0075] The chamber 78 of the second connector part 8 is divided into anouter sub-chamber 108 and four inner sub-chambers 110. Each innersub-chamber 110 is defined within an inner bladder 112 which extendsforwardly from the rear wall 98. The inner bladder 112 has a thick frontwall 114 formed with an opening 116 through which the shuttle piston 92passes in sealing manner. The inner bladder 112 has a circumferentiallyextending thinner side wall 118, the outside of which is exposed to thepressure in the outer sub-chamber 108, thereby allowing pressureequalisation of the inner sub-chamber 110 relative to the outersub-chamber 108. The inner bladder 112 is supported at its front end ona sleeve 120 around the shuttle piston 92. The sleeve 120 is formed witha slot opening 122 allowing optical contact socket 84 to be positionedin close proximity to the shuttle piston 92 and, as will be describedlater, to allow the optical contact pin 21 of the first connector partto gain access to the optical contact socket 84. The inner bladder 112includes a tubular side portion 121 which receives the optical contactsocket 84.

[0076] The shuttle piston 92 is forwardly biased by a spring 124 so thatin the unmated condition of the second connector part 8 shown in FIG. 7the shuttle piston blocks and closes opening 90, which forms theentrance to the fluid filled chamber 78, and the opening 116, whichforms the entrance to the inner sub-chamber 110 of the chamber 78.

[0077] The connection procedure of the first and second connector partswill now be described. The connector parts are brought into axialinterengagement by relative axial movement towards each other. The plug6 of the second connector part enters the receptacle 4 of the firstconnector part, such that the front wall 88 of bladder 86 makes contactwith the front wall 38 of bladder 36. With continued interengagement,the plug 36 pushes the shuttle 24 rearwardly (to the left as shown inthe drawings) against the bias of spring 26. At this time, the slidingsleeve 206 of the probe 10 holds its position relative to the receptacle4, under the influence of spring 208. The probe 10 pushes shuttle piston92 rearwardly of the plug 6 against the bias of spring 124. The spring208 therefore has a greater spring constant than spring 124, preferablyby a substantial margin.

[0078] With continued interengagement the connector parts reach anintermediate position as shown in FIG. 13. At this stage springs 26 and124 have been compressed a considerable amount, but spring 208 has notbeen compressed and has held the sliding sleeve 206 of the probe 10 inits initial forward position.

[0079] With further interengagement of the connector parts, the plug 6urges the shuttle 24 further rearwardly in the receptacle 4,additionally compressing spring 26. The shuttle 24 pushes on the rearshoulder 207 of the sliding sleeve 206 so as to urge it rearwardly inthe receptacle and compress spring 208. The shuttle piston 92 is pushedrearwardly by the probe 10, further to compress spring 124. Once theseactions are completed the connector parts are fully mated, as shown inFIG. 14.

[0080] At the intermediate stage shown in FIG. 13 the contact pin 21 ofoptical contact 20 is fully disposed inside slanted passage 22 of probe10 and does not protrude therefrom. Therefore, up until this point,during the mating procedure, the probe 10 passes through the openings 64and 40 in the front walls 62 and 38 of the receptacle bladders 60 and 36respectively, and through the openings 90 and 116 in the front walls 88and 114 of the bladders 86 and 112 respectively, without the opticalcontact pin 21 interfering with the passage of the probe through thoseopenings. The probe 10 slides axially through these openings in slidingengagement with the respective seals as the nose portion 200 and probecontact portion 202 advance into the chamber 78 of the second connectorpart 8. Subsequently, as the sliding sleeve 206 of the probe 10 is urgedrearwardly from the position shown in FIG. 13 to that shown in FIG. 14,the slanted passage 22 in the sliding sleeve 206 moves rearwardly alongthe optical contact support tube 212. The rear of this tube isrestrained from axial movement relative to the receptacle by theengagement of the lugs 214 in the transverse slots 216 of the conductivearms 204, whilst transverse movement is permitted. Thus the rearwardmovement of the sliding sleeve 206 causes, by a camming action, alateral movement of the optical contact support tube.

[0081] The rearward movement of the sliding sleeve 206 also results init separating from the probe contact portion 202 and uncovering thefront opening 27 of passage 22. The contact pin 21 emerges from frontopening 27 of passage 22 and slides into contact socket 84 to establishthe optical coupling laterally outwardly of the probe. The contact pinis thus first “carried” by the probe from the first connector part tothe second connector part, whereafter the optical coupling isestablished in the second connector part.

[0082] As far as making an electrical connection is concerned, this isnot established at the intermediate stage shown in FIG. 13, but isestablished when the shuttle piston 92 has been urged further rearwardlyto the fully interengaged condition shown in FIG. 14. At this time theelectrical probe contact portion 202 engages in the electrical contactsocket 130 of the plug 6.

[0083] The above described embodiment is a four probe connector,allowing four optical couplings and four electrical couplings to beestablished. However, the same principles of operation are applicable toa single probe connector, or connectors with different numbers orprobes.

[0084] FIGS. 17 to 19 show another embodiment in which the samereference numerals are used to designate the same parts as theembodiment of FIGS. 1-15. This embodiment differs however in that theoptical contact 20 is carried by a rigid tube 250 which is itselfsupported at the front of a flexible tube 252. The rearward movement ofthe sliding sleeve 206 relative to the rest of the probe 10 causes theflexible tube 252 to flex as necessary for the optical contact pin 21 toemerge from the front opening 27 of the passage 22 to establish theoptical coupling.

[0085] The manner of operation of the embodiment of FIGS. 17 to 19 isotherwise substantially the same as that of FIGS. 1 to 15.

[0086]FIGS. 20a-20 d show schematically the manner of operation ofanother embodiment. In this case the probe 10 comprises an inner body142 and an outer sleeve arranged axially slidably relative to the innerbody. A spring 146 biases the outer sleeve 144 to a forward positionrelative to the inner body 142 when the connector parts are unmated, asshown in FIG. 20a. At this time the front side opening 27 of the probe10 is closed by the outer sleeve 144.

[0087] The connection procedure is shown in FIGS. 20a-20 d. As seen inFIG. 20b, the front walls 38 and 88 of the respective chambers 34 and 78are brought together and the front of the probe 10 engages the front ofthe shuttle piston 92. With further axial interengagement the spring 124biasing the shuttle 92 compresses, allowing the probe 10 to pass throughthe opening 90 into the chamber 78. As seen in FIG. 20c, the outersleeve 144 of the probe remains in its forward, closing position as theprobe advances through the opening 40 of the chamber 34 and through theopening 90 of the chamber 78. Thus, a good seal between the probe andthe front walls 38 and 88 is maintained during connection.

[0088] Once the front side opening 27 has entered the chamber 78, withcontinued axial interengagement, the outer sleeve 10 is urged rearwardlyrelative to the sleeve inner body 142 against the bias of the spring 146and the outer sleeve 144 is retracted to uncover and open the front sideopening 27. This is shown in FIG. 20d. The advancement of the opticalfibre 16 out of the side opening takes place by compression of a spring18 and forward movement of the optical contact 20.

[0089] In a modification of the embodiment of FIGS. 20a-20 d, a sealcould be fitted between the outer sleeve 10 and the inner body, toprovide an extra barrier against sea water. For example an O-ring sealcould be provided on the inner body 142 so as to be in sealingengagement with the front of the outer sleeve 144 when in its closedposition.

[0090] The embodiment of FIGS. 21a-21 d, 22 and 23 is similar to that ofFIGS. 20a-20 d, except that the inner body 142 is arranged to rotatewithin the outer sleeve 144 to uncover and open the front side opening27. As seen in FIG. 22, which shows the outer sleeve 144 alone, thisincludes an angled profile 146 at its front end, and as seen in FIG. 23,which shows the probe inner body 142 alone, this has a rearwardly facingcorrespondingly angled profile 148. As seen in e.g. FIG. 21a, the sleeve150 which houses the spring 124 for the shuttle piston 92 is formed witha key way 152 which extends rearwardly first axially and then axiallywith a circumferential component. The shuttle piston 92 is provided witha radially outwardly projecting key 153 which engages in the key way.The front of the shuttle piston 92 is formed with an oblong slot 154 forreceiving a corresponding oblong projection 156 at the front end ofprobe 10. The projection and slot are engageable such that the probe andthe shuttle piston are non-rotationally connected.

[0091] The connection sequence is shown in FIGS. 21a-21 d. When thefront walls 38 and 88 of the respective chambers 34 and 78 come togetherthe projection 156 locates in the slot 154, as seen in FIG. 21b. At thisstage the front side opening 27 of the probe 10 faces downwardly (asshown by way of example in the drawing) and the outer sleeve 146advances through the openings 40 and 90 of the chambers 34 and 78 whilstmaintaining the closed position. There is no rotation of the shuttlepiston 92, and hence of the inner body 142 of the probe, at this time asthe key 153 remains in the axially extending part of the key way 152.

[0092] With continued axial interengagement the key starts to move alongthe part of the key way which extends circumferentially, causing theshuttle piston 92 to rotate and in turn causing the inner body 142 ofthe probe 10 to rotate. The rearwardly facing angled profile 148 of theinner body 142 acts on the forwardly facing angled profile 146 of theouter sleeve 144, such that the inner body is advanced forwardlyrelative to the outer sleeve, against the bias of spring 146. The frontside opening 27 in the passage 18 undergoes a half turn so as to faceupwardly. Because of the angled profile 146 of the outer sleeve 144,when the inner body turns to this position the front side opening 27 isno longer covered by the outer sleeve and hence the optical pin 21 isable to emerge from the passage 18 to establish the optical coupling.

[0093] As with the embodiment of FIGS. 20a-20 d, the embodiment of FIGS.21a-21 d, 22 and 23 allows the two front walls 38 and 78 to act on afull cylindrical probe at all times, thereby improving the sealingproperties of the connector during the connection procedure.

[0094]FIGS. 24a-24 d show schematically another embodiment at stagesduring the connection procedure. In this embodiment the probe 10 has ahinged portion 160 which is biased by a spring (not shown) to an openposition. As seen in FIG. 24a, the hinged portion 160 is held shut byengagement with the edge of the opening 40 of the bladder front wall 38.Once the hinged portion 160 has passed through the opening 40 andfurther through the opening 90 in the front wall 88 of the secondconnector part 8, it springs open to allow the optical contact 21 toemerge from the front side opening 27 of the probe and establish opticalcontact with the optical contact side 84.

[0095] Generally, in the preferred embodiments, an optical coupling ismade between a first optical member, in the form of optical contact 20,and a second optical member, in the form of optical contact 80. Thecoupling is made possible by the entry of the probe 10 to the chamber78, whereby the probe provides an optical path between the connectorparts. Once this path is provided, the exact location of the opticalcoupling is not critical. Although it is shown in the preferredembodiments as taking place in the chamber 78, the optical couplingcould alternatively be made in the e.g. passage 22 of the probe and/orin the chamber 34.

[0096] The slant of the optical path to the axial direction where itpasses through the side of the probe will generally be substantiallyless than 90°. This avoids the optical fibres 16 and 76 leading to theoptical contacts 20 and 80 respectively having to turn through asubstantial angle from the axial direction to the direction of theoptical path where it passes through the side of the probe. There isusually a maximum curvature to which optical fibres may be subjectedwithout signal attenuation or other problems, so that if an opticalfibre is turned through a large angle this adds to the spacerequirements in the lateral direction. For this reason, smaller slantangles are advantageous, as the width of the connector can be kept to aminimum.

[0097] In the preferred embodiments, a small slant angle to the axialdirection also assists location of the optical contact pin 21 in theoptical contact socket 84 during interengagement. It will be appreciatedthat the positions of the contact pin and contact socket could bereversed, with the pin being located on the plug 6 and the socket on thereceptacle 4.

[0098] The slant angle to the axial direction is preferably less than60°, more preferably less than 45°, more preferably less than 30°.

[0099] There are various advantageous features in the embodimentsdescribed herein. It will be understood that features from differentembodiments may be combined in combinations which are not shown in thedrawings. For example the provision of a means of covering the opticalcontact in the probe until it has entered the second connector part maybe used in embodiments having outer and inner sub-chambers in the firstconnector part and/or the second connector part. The covering featuremay also be combined with the use of a probe which provides both anoptical and an electrical connection. Many other combinations are ofcourse possible, and the embodiments should be considered asillustrative and not limiting of the scope of the invention.

1. A connector for making an optical connection underwater or in a wetenvironment, comprising first and second connector parts adapted to beinterengaged, the first connector part having a first optical member forestablishing an optical coupling with a second optical member of thesecond connector part when the connector parts are interengaged, thefirst connector part having a probe and the second connector part havinga chamber containing fluid media and being provided with a seal definingan opening thereto, wherein the probe has a forward portion for entryinto the chamber of the second part containing fluid media duringinterengagement of the connector parts, so that when the connector partsare interengaged the probe provides an optical path between the firstconnector part and the chamber of the second connector part and therebyallows the first and second optical members to establish said opticalcoupling, said optical path extending from the first connector partalong the probe and passing into the chamber of the second connectorpart at a slant to the axial direction, and wherein duringinterengagement of the connector parts the probe slides axially throughthe opening in sliding engagement with the seal and continues to do soas the forward portion of the probe advances into the said chambercontaining fluid media.
 2. A connector as claimed in claim 1, whereinthe first optical member is disposed internally of the probe at leastduring the passage of the forward portion of the probe through the sealof the second connector part.
 3. A connector as claimed in claim 1 or 2,wherein the probe comprises relatively movable parts arranged to enclosethe first optical member when the first and second connector parts arenot interengaged and arranged to open after the probe has entered thechamber of the second connector part to allow the optical couplingbetween the first and second optical members to be established.
 4. Aconnector as claimed in claim 1, 2 or 3, comprising a first springarranged to deform during a first phase of interengagement of theconnector parts until the forward portion of the probe is located in thechamber of the second connector part containing fluid media, and asecond spring arranged to deform during a second phase ofinterengagement of the connector parts to permit the forward portion ofthe probe to advance forwardly relative to a rear portion and therebyallow the optical coupling between the first and second optical membersto be established.
 5. A connector as claimed in any preceding claim,wherein, after the probe has entered the chamber of the second connectorpart, at least one of the first and second optical members is arrangedto move from a retracted position to a coupling position.
 6. A connectoras claimed in claim 5, wherein the first optical member is arranged tomove relative to a guide portion of the probe during interengagement ofthe connector parts, the guide portion being arranged to urge the firstoptical member laterally outwardly of the probe from a retractedposition to a coupling position during said interengagement.
 7. Aconnector as claimed in claim 6, wherein the probe has a surface slantedrelative to the axial direction which guides the first optical member tothe coupling position.
 8. A connector as claimed in any preceding claim,wherein the second connector part comprises pressure balancing means forallowing pressure in the chamber to balance relative to externalpressure.
 9. A connector as claimed in any preceding claim, wherein thechamber of the second connector part comprises an outer sub-chamber andan inner sub-chamber.
 10. A connector as claimed in claim 9, wherein theouter sub-chamber is provided with said seal defining said chamberopening, and the inner sub-chamber is provided with a seal defining aninner sub-chamber opening, and wherein during interengagement of theconnector parts the probe slides axially through the outer and innersub-chamber openings and in sliding engagement with their respectiveseals, whilst the forward portion of the probe advances into the innersub-chamber.
 11. A connector as claimed in claim 9 or 10, wherein thesecond connector part comprises a plurality of inner sub-chambers, eachprovided with a respective seal defining a respective inner sub-chamberopening, and wherein the first connector part comprises a plurality ofprobes each for advancement during interengagement of the connectorparts into a respective inner sub-chamber of the second connector partto establish a plurality of optical couplings.
 12. A connector asclaimed in any preceding claim, wherein the first connector partcomprises a probe chamber in which the first optical member is disposedwhen the connector parts are not interengaged, the probe chamber and theprobe being relatively axially movable to allow the probe to emerge fromthe probe chamber during interengagement of the connector parts, and theprobe chamber containing fluid media.
 13. A connector as claimed inclaim 10, wherein the first connector part further comprises pressurebalancing means for allowing pressure in the probe chamber to balancerelative to external pressure.
 14. A connector as claimed in claim 12 or13, wherein the probe chamber comprises an outer sub-chamber and aninner sub-chamber.
 15. A connector as claimed in claim 14, wherein theouter and inner sub-chambers of the probe chamber are provided withrespective seals defining respective openings thereto, and whereinduring interengagement of the connector parts the probe slides axiallythrough the inner and outer probe sub-chamber openings in slidingengagement with their respective seals.
 16. A connector as claimed inany of claims 12 to 15, wherein the chamber of the second connector partand the probe chamber of the first connector part are sealed from eachother when the first and second connector parts are interengaged.
 17. Aconnector as claimed in any preceding claim, wherein the probe isprovided with a first electrical contact portion, and the secondconnector part has a second electrical contact portion, the first andsecond electrical contact portions being arranged to make electricalcontact when the connector parts are interengaged.
 18. A connector asclaimed in any preceding claim, wherein the second connector part isprovided with a shuttle piston resiliently biased to a forward positionin which it engages a radially inwardly facing surface of the seal so asto close the opening defined thereby when the connector parts aredisengaged, the shuttle piston being arranged to be engaged by the probeand urged rearwardly during interengagement of the connector parts, theprobe then engaging the radially inwardly facing surface of the seal soas to close the opening defined thereby.
 19. A connector for making anoptical connection underwater or in a wet environment, comprising firstand second connector parts adapted to be interengaged, the firstconnector part having a first optical member for establishing an opticalcoupling with a second optical member of the second connector part whenthe connector parts are interengaged, the second connector part having achamber containing fluid media and being provided with a seal definingan opening thereto, and the second connector part being provided with ashuttle piston resiliently biased to a forward position in which itengages a radially inwardly facing surface of the seal so as to closethe opening defined thereby when the connector parts are disengaged, andthe first connector part having a probe for entry into the chamber ofthe second part containing fluid media during interengagement of theconnector parts, the shuttle piston of the second connector part beingarranged to be engaged by the probe and urged rearwardly during saidinterengagement, the probe then engaging the radially inwardly facingsurface of the seal so as to close the opening defined thereby, and,when the connector parts are interengaged, the probe providing anoptical path between the first connector part and the chamber of thesecond connector part to allow the first and second optical members toestablish said optical coupling, said optical path extending from thefirst connector part along the probe and passing into the chamber of thesecond connector part at a slant to the axial direction.
 20. An opticalconnector for making an optical connection underwater or in a wetenvironment, comprising a probe on a first connector part arranged topass through a seal on a second connector part, so as to provide anoptical path which extends through a side of the probe.